Lemon
 |
A Kepler. 
It consists of less than half of a circularArc rotated about an axis passing through the endpoints of the Arc. The equations of the upper and lowerboundaries in the 
plane are
for
and 
. The Cross-Section of a lemon is a Lens.The lemon is the inside surface of a Spindle Torus.See also Apple, Lens, Spindle Torus- Factorial Prime
- Factorial Sum
- Factoring
- Factorion
- Factorization
- Factor Level
- Factor Ring
- Factor Space
- Fagnano's Point
- Fagnano's Problem
- Fagnano's Theorem
- Fair Game
- Fairy Chess
- Fallacy
- False
- False Position Method
- Faltung (Form)
- Faltung (Function)
- Fan
- Fano Plane
- Fano's Axiom
- Farey Sequence
- Farey Series
- Farkas's Lemma
- Faro Shuffle